According to SamMobile report, the Android 4.4.2 XXUFNA5 KitKat test firmware brings a host of bug-fixes and feature enhancements over its previous test build.

Samsung Galaxy S4 (LTE) I9505 users can now update their devices with the leaked version of Android 4.4.2 KitKat firmware by following the tutorial below.

Pre-requisites
1. Install USB Drivers for Samsung Galaxy S4 on the computer.
2. Enable USB Debugging Mode on the phone by navigating to Settings >> Developer Options.
3. Make a backup of all your important data before following the guide.
4. The Galaxy S4 should be factory unlocked and not locked to any particular carrier.
5. Ensure the battery of the phone is charged more than 80 percent.
6. The Android 4.4.2 XXUFNA5 KitKat firmware is compatible only with the LTE version of Samsung Galaxy S4 (GT-I9505). Applying this to any incorrect variant might brick the device. Verify the model number of the Galaxy S4 by navigating to Settings >> About Phone.

Files Required
1. Android 4.4.2 XXUFNA5 KitKat Firmware for Galaxy S4 (LTE) I9505
2. Odin 3.09 (Mirror Link)Steps to Update Galaxy S4 (LTE) I9505 with Android 4.4.2 XXUFNA5 KitKat FirmwareStep 1: Extract Firmware zip file using WinRAR/7-Zip/WinZip or any other extracting tool.Step 2: Extract Odin zip file and you will get Odin3 v3.09.exe along with few other files.Step 3: Switch off the Galaxy S4.Step 4: Boot the device into Download Mode by pressing and holding Volume Down, Home and Power buttons together until a construction Android robot icon with a warning triangle appears on screen. Now press the Volume Up button to enter Download Mode.Step 5: Run Odin on the computer as an Administrator.Step 6: Connect the Galaxy S4 to the computer using USB cable while it is in the Download Mode. Wait until Odin detects the device. When the device is connected successfully, the ID: COM box will turn to light blue with the COM port number. Additionally, the successful connected will be indicated by a message saying Added.

Note:If the Added message does not appear, then try re-install USB drivers or changing the port on the computer.

Step 7: Select the following files in Odin from extracted I9505XXUFNA5 firmware folder:

Click the BL button and select file with BL in its name.

Click the AP button and select file with AP in its name.

Click the CP button and select file with CP in its name.

Click the CSC button and select file with CSC in its name.

Step 8: In Odin, enable Auto Reboot and F. Reset Time checkboxes. Also, ensure the Re-Partition option is NOT selected.Step 9: Verify everything suggested in Step 7 and Step 8 is done correctly. Then hit the Start button to begin the installation process.Step 10: Once the installation process completes, your phone will restart and soon you will see a PASS message with green background in the left-most box at the very top of the Odin. You can now unplug the USB cable to disconnect your device from the computer.

Samsung Galaxy S4 (LTE) I9505 should be now updated with leaked Android 4.4.2 XXUFNA5 KitKat firmware. Head over to Settings >> About Phone to verify the software version running on the device.

Note:If Galaxy S4 (LTE) I9505 stuck at booting animation after Step 10 then go to recovery mode (press and hold the Volume Up, Home and Power buttons together) and perform Wipe data/Factory Reset and Wipe Cache Partition task before selecting reboot system now function. In recovery mode use Volume keys to navigate between options and Power key to select the option. Please note, performing wiping task will erase your device internal memory data and not external SD card data.